These conditions are arguably some of the stranger diagnoses tossed around in medical discourse, so it should come as little surprise if you've never spoken with your doctor about them. But however strange they may seem, many medical professionals say that these disorders are legitimate conditions that can warrant treatment.

Yet, acceptance from part of the medical community has not stopped debates on the existence of many of these conditions.

"Illness is always a social construct," noted Dr. Nortin Hadler, professor of medicine and microbiology/immunology at the University of North Carolina at Chapel Hill and author of the book "Worried Sick: A Prescription for Health in an Overtreated America."

"People have to agree -- both people, in general, and those in the medical community -- that a life experience should be labeled an illness," Hadler said. "For example, the Victorians medicalized orgasm, and we medicalize the lack of it."

Dr. Igor Galynker, director of The Family Center for Bipolar Disorder at Beth Israel Medical Center in New York, said that psychiatric conditions in particular tend to attract controversy.

"In psychiatry, part of a disorder is clinically defined and part is societally defined," he said, adding that conditions, such as Attention Deficit Disorder, or ADD, are particularly contentious.

"An ADD diagnosis is very controversial, especially after a recent paper suggested some children with ADD 'grow out' of it at age 25," he said. "That would mean that ADD is a phase in development, rather than a disease. ... It is all fluid."

But not all medical experts believe many of these disorders should be dismissed so readily by the public.

"Individuals should not think these disorders are trivial," said Dr. David Kupfer, a clinical professor of psychiatry at the University of Pittsburgh Medical Center, who is part of the team charged with drafting the new Diagnostic and Statistical Manual of Mental Disorders (DSM), a periodically updated compendium of psychological conditions for professional reference. "They are real. By having them in the DSM, hopefully it makes the stigma less."

The following are just a few of the many controversial diagnoses in the medical literature today.

Post-Traumatic Embitterment Disorder

For those who have been laid off from a job, gone through a divorce or had a loved one die, that seething, bitter feeling inside might have a name: Post-Traumatic Embitterment Disorder (PTED).

First identified by German psychiatrist Dr. Michael Linden following the fall of the Berlin Wall in immigrants from East Germany, PTED shares many of its characteristics with post-traumatic stress disorder, with the notable exception that the stress trigger is not life-threatening.

Linden reported in a 2003 article in the journal Psychotherapy and Psychosomatics that people suffering from PTED also suffer significant feelings of injustice, sadness, rage and helplessness, and they dwell on these feelings so much that performance in daily activities suffers.

Dr. Barbara Rothbaum, professor of psychiatry and director of the Trauma and Anxiety Recovery Program at the Emory School of Medicine in Atlanta, pointed out that it may be useful to differentiate between PTED and other types of stress disorders in terms of treatment.

"The mechanism behind anxiety and anger and what you do about them is different," Rothbaum said. "With anxiety, you do exposure therapy and help a person confront what they're scared of in a therapeutic manner. That's not the way anger works. The more you focus on it, the more angry you get. ... You want to see people move through [those feelings] and not get stuck in it."

Except for Linden, few have researched the psychology of lasting bitterness, and little evidence exists about the difference between PTED and the existing cadre of trauma and stress disorders.

"Whether or not [PTED] is different from PTSD is something the DSM committee needs to think about," said Dr. Anand Pandya, vice chair of the Department of Psychiatry at Cedars-Sinai Medical Center in Los Angeles.

Pandya pointed out that, for example, some people with depression cry often and others with depression do not.

"The realities are that any clinician who's treated trauma survivors knows that very often people have a variety of emotional reactions, complex emotions like bitterness," Pandya said. "The question is: Does that difference make a difference?"

Intermittent Explosive Disorder

Imagine, for a moment, the worst manifestations of aggression: domestic abuse, road rage, a tendency to pick fights for no good reason. While to some, such behavior would constitute a mere personality problem, to others it suggests a psychological condition known as intermittent explosive disorder.

"The way [intermittent explosive disorder] is described right now, it refers to somebody who repeatedly fails to control their aggressive drive," Galynker said. "They may act completely out of proportion to a situation."

And while the diagnosis may sound odd, it may be more common than you think. A June 2006 study funded by the National Institute of Mental Health found that intermittent explosive disorder may affect as many as 7.3 percent of adults in the United States, mostly men.

While these people may fly into uncontrolled rage on a fairly regular basis, many feel remorse or embarrassment for their actions afterward. For this reason, Galynker added that intermittent explosive disorder can be thought of most effectively as an "aggression disregulation" and that a lot of people have gradations of it.

But is it for real? Galynker, for one, thinks so. And he says those who live with Intermittent Explosive Disorder often experience the consequences of their rage.

"A lot of people can't manage their aggression, and a lot of them end up in jail after an explosion," he noted.

But, as with many such disorders, some people may question whether someone who has been diagnosed with such a condition should be held fully responsible for their actions. Indeed, while some may argue that applying such diagnoses to this type of disposition could give some people a blank check for bad behavior, others might say the condition could warrant leniency.

Galynker, however, is adamant that an intermittent explosive disorder diagnosis should not be enough to get someone off the hook for hyperaggressive behavior.

"The fact that people can't control their behavior doesn't mean that they are not responsible for their behavior," he says.

A number of different drugs are used to treat intermittent explosive disorder, including anti-anxiety medications, like Valium and antidepressants, like Prozac. Psychiatrists have also used behavioral therapy to treat those with the condition.

Morgellons Syndrome

Perhaps one of the strangest and most controversial medical mysteries out there today, Morgellons syndrome involves the sprouting of inorganic material -- including fibers and crystals -- from the skin.

No solid evidence yet exists for the condition, and many doctors today say it is likely more a psychological condition than a physical one. That is, of course, assuming that the individuals who say they suffer from it do not actually have these objects growing from their skin.

And while most medical professionals doubt the existence of the condition, at least one -- pediatrician Dr. Greg Smith of Gainesville, Ga. -- claims to actually have experienced the condition firsthand.

"It felt like somebody stuck a pin in my toe and wiggled it and it just continued to hurt," Smith told ABC News in 2006. "I've certainly had those crawling sensations, and the fibers which come out of the skin are really bizarre, and really odd."

However, Dr. Vincent DeLeo, chief of dermatology at New York's St. Luke's-Roosevelt Medical Center, weighed in on what he'd say to someone who came to him with this condition: "I don't think this is any different than many patients I've seen who have excoriations and believe that there is something in their skin causing this."

Maybe you never got along with your little brother or sister. Perhaps numbers make your stomach turn, or maybe you drink a bit too much coffee for your own good.

If you're like most people, none of these situations poses a real threat to your daily routine. But take any of these situations and imagine them magnified exponentially. Suddenly, you're dealing with Sibling Rivalry Disorder, Mathematics Disorder or one of any number of Caffeine-Related Disorders.

Like some of the other diagnoses on this list, these conditions appear in one form or another in the DSM. And Kupfer says there is a good reason for including them; specifically, he says these collections of symptoms can often cause a certain level of personal distress or impairment -- the very definition of a disorder.

"In a way, what we are looking for is to diagnose things reliably to allow individuals to seek treatment," Kupfer says.

With regard to Sibling Rivalry Disorder, treatment can mean counseling that could solve family problems or prevent future psychological conditions. Teaching someone to cope with caffeine abuse may save them from sleep-related problems. It is in these situations, Kupfer says, that labeling such conditions as disorders is helpful.

And as far as Mathematics Disorder goes, most are skeptical that receiving such a diagnosis will get you much pity from your teachers.

"Would anybody actually say, 'I have math disorder and I'm getting treatment, and that's why I'm not successful'?" asks Dr. Dost Ongur, clinical director of the schizophrenia and bipolar disorder program at Harvard University's McLean Hospital in Belmont, Mass. "No, you would never get something like that. Math disorder is not like diabetes."

Oppositional Defiant Disorder (ODD)

Oppositional Defiant Disorder, or ODD for short, is a diagnosis that is applied to children who display such frequent and aggressive defiance of their parents that it disrupts the lives of those within the family.

According to the Mayo Clinic Web site, as many as one in 10 children may have oppositional defiant disorder in a lifetime, and it is often associated with other childhood behavioral disorders, such as ADD.

Galynker says the roots of this disorder are most likely genetic; aggression, he says, is one of the most highly inherited qualities. And genetic links to the kind of aggression seen in children with ODD have been proven in twin studies. Based on this, he says, ODD is likely a very real disorder.

"It's their internal characteristic to argue with their parents," he says. "Some deal better with this, while others deal worse."

An official diagnosis of ODD would likely be met first with counseling, and later with medications to help control a child's behavior. Parents may also receive counseling in order to learn more about how to control their children's behavior.

But many would argue that the blame should be more squarely placed on nurture than nature -- in order words, that parenting styles are more likely to be responsible for this disorder than genes. Ongur says it is little surprise that this may be the commonly held perception.

"For these disorders, I think it makes sense for the lay person to have that kind of reaction -- not because they are fake disorders, but because of the way it plays out in society," he notes.

Hadler, however, has a different take -- that ODD is yet another example of the medicalization of commonly seen behavior.

"No young child can be a brat anymore," he says. "Now, what right do we have to do that?"

Dissociative Fugue State

The stories are rare, but they are out there.

A successful lawyer -- a husband and father of two, active in his community -- disappears, only to be found six months later, living in a different city under a new name in a homeless shelter.

A man without an identity walks into a hospital, saying he woke up on the street with no wallet or identification, and says he has no idea who he is. His family locates him two weeks later, after which he returns to normal.

Such cases are examples of dissociative fugue state. In these cases, an individual will disappear, leaving everything behind -- including their memories and identity. In some cases, the sufferer even assumes a new identity, which persists until they are reunited with their old surroundings and allowed to return to their old persona.

Few psychological disorders have attracted such wonder from the public -- and sparked so much debate among experts in the field. Nowadays, most psychological experts agree that such cases are not simply about individuals running away from their problems, but, rather, a legitimate condition.

"The thing that people experience as 'fugue state' does happen," Ongur says. "There are people who wake up in other cities and don't know what has happened."

The fugue state is actually part of a larger family of conditions known as dissociative memory disorders. The trigger for these conditions is usually a traumatic event -- the death of a loved one, for example, or an extraordinarily stressful event at work. It is also more common in those who bear past trauma from events like natural disasters and war.

Chronic Fatigue Syndrome (CFS)

Chronic Fatigue Syndrome, or CFS, has garnered additional support as a legitimate diagnosis in recent years. Today, the U.S. Centers for Disease Control and Prevention (CDC) recognizes it as a condition that affects between 1 million and 4 million Americans.

Of these individuals, according to the CDC, only about half have consulted a physician for their illness -- even though it has been known to cause serious impairment in some.

As the name implies, CFS is most often associated with severe, debilitating fatigue. Non-specific pain and other symptoms are also common hallmarks of the condition, which is disproportionately experienced by women. As the condition persists, patients will often become depressed at the current lack of proven treatments to remedy the problems they experience.

But while the condition is starting to receive more attention and support, the underlying causes largely remain a mystery. Some have cited Epstein-Barr virus as a likely culprit. Others point to anemia, while still others implicate allergies.

Perhaps it is for this reason that the borders of this diagnosis remain contentious at best. Symptoms run the gamut from long-lasting flu-like symptoms to memory loss. Treatment can involve antidepressants, antihistamines or acupuncture.

To Hadler, CFS seems less like an actual condition and more like a rapidly growing hodge-podge of symptoms associated with a number of different diagnoses that are becoming increasingly more prevalent.

"Now it overlaps with post-traumatic stress disorder, fibromyalgia -- all of these labels include symptoms of fatigue," he says.

Still, dozens of studies -- many federally-funded -- are seeking answers as to the true nature of this condition.

Multiple Personality Disorder

It's been the stuff of horror movies and big-screen comedies. Yet, the truth behind Multiple Personality Disorder -- or Dissociative Identity Disorder (DID), as it is known today -- is, in most cases, a far cry from these dramatic interpretations of this classic psychological condition.

"Even when a patient says it's a different personality, it's nothing magical," Ongur says. "When people describe it, it is really a very extreme version of the more familiar feeling of disintegration. If you are under extreme stress or have had certain past experiences, the way the mind functions may actually break down."

Those who experience DID will create at least one "alter" personality that manifests itself in certain situations -- in essence, "taking control" of one's personality. These changes occur involuntarily, and DID in its most severe forms can limit one's ability to interact with others.

By the same token, the condition can occasionally go mostly unrecognized. Football great Herschel Walker is just one example; in his recently released book, "Breaking Free: My Life with Dissociative Identity Disorder," Walker says his life was fragmented by a number of independent "alters" -- at least one of which led him to attempt suicide.

Ongur says early psychological trauma is one of the most common underlying causes of the disorder.

"When people describe these things, it is certainly often associated with a severe history of child abuse," he says. "This was one way for them to cope."

And, as in Walker's case, psychological treatment involves unifying the alters into a single personality -- allowing those who suffer from the condition to regain full control over their lives.

"The task is to get this person feeling whole again," Ongur says.

Social Anxiety Disorder (SAD)

If there is a success story among psychological conditions once considered spurious, it is that of Social Anxiety Disorder (SAD), psychological experts say.

"The whole issue of social phobias was once considered something that was not very important," Kupfer says. "As we discovered, this can cause a tremendous amount of impairment, and there are a whole lot of issues developmentally which affected coping with it."

In labeling this as a disorder, he says, medical professionals have been able to help millions of people who otherwise would have been told that they were simply shy.

Ongur agrees. "It's familiar to people because it's shyness, but it's really extreme shyness," he says. "It is something that can be very real and very impairing."

Those who suffer from SAD often find themselves faced with seemingly insurmountable anxiety when it comes to interacting in certain social situations. Most common are feelings of being watched, scrutinized and criticized by others. So intense is this anxiety that it can sometimes lead to a panic attack.

In most cases, these fears are unreasonable. Counseling can often help those who live in near-constant fear of being embarrassed or humiliated in front of others. Coaching in social skills may also be needed in order to help those with SAD better integrate themselves into comfortable social circles.

"Social phobia ... is a relatively new diagnosis," Galynker says. "Many people have difficulty socializing, of course. This is just a label to help treat people who have it."

And Galynker says the changing perception of SAD and psychological conditions like it will hopefully help remove the stigma so often associated with such disorders.

"Everybody has a problem, really," he says. "Nobody does not have some sort of diagnosis."